Popeyes has opened a new outlet and yes, it is in the airport again which I can't understand why they can only be found at the 3 terminals and not anywhere else in Singapore. In T3, it is located just next to the Kopitiam foodcourt at Basement 2.
For a 4-piece set meal ($13.95), it comes with 4 pieces of chicken, 2 drinks, 3 side dishes and 2 biscuits (and jam). Side dish selection include fries, mash potato, coleslaw or redbean rice. Not all may like the red-bean rice cos the taste is a little unusual. You'd either love it or hate it.